Multistage gas turbine



p 9, 1930- H. HOLZWARTH I MULTISTAGE GAS TURBINE Original Filed Aug. 17 1926 H RW 2 N TL R W m V//7 T Mv m Patented Sept. 9, 1930 UNITED STATES PATENT" oar-lea L 5 HANS HOJLZWABTH, F DUSSEBDOBF, GERMANY, ASSIGNOB '10 HOLZWAB'I'H GAS TUB- BINE 60., 0F FRANCISCO, CALIFORNIA, A CORPORATION OF DELAWARE uunrrsraon .oas runnnm Application fled August 17, 1826, Serial No. 129,740. Renewed. February 8, 1980.

My present invention relates to a power plant in which combustion gases obtained by the explosion of a mixture of fuel and air are employed to o erate the rotor of a turbine in conjunctionkwlth steam, and in which the remaining ener of the steam and of the combustion gases 1s utilized in an efiicient way for the production of additional power. A satisfactory and preferred form of my v present invention will now be described in detail with reference to the accompanying drawings, in which Fig. 1 is an elevation of the plant with parts in section along the line 1-1 of Figs. 2 and 3, duplicates in elevation ll of parts appearing in section being omitted for the sake of clearness; Fig. 2 is a cross-section on line 2-2 of Fig. 1; and Fig. 3 is a section along the line 3-3 of Fig. 1. At 1 I have indicated the explosion chamber in which the combustion gases are produced. The engine may have one chamber of this character or a plurality of them. Suitable inlet valves, are provided for the admission of air and fuel respectively and an outlet 15 valve 1 is provided 1n conjunction with such explosion chamber, said outlet valve being arranged in a ring 2 interposed between the combustion chamber or cliambersand the high pressure rotor 3 and provided with one or 80 more nozzles 4 to discharge the successive 'jets of combustion gases resulting from the successive explosions against the blades of said rotor. Any suitable mechanism is provided for operating the inlet and outlet valves at the proper times and for igniting or exploding the combustible mixture. After issuing from the nozzles 4, the combustion gases, as they issue from the blade channels of the rotor 3. are received in an exhaust chamher 5 which is in direct communication with the inlet of an intermediate pressure turbine 6 of any suitable construction, but preferably of the multi-stage type which embodies a suc O cession of rotor rings alternating with stator rings. At the outlet end of thev intermediate pressure turbine 6, the combustion gases pass out through a pipe 7 and give off part of their heat to a boiler 7 whereupon they escape to the atmosphere. In said boiler, high pressure steam is generated and superheated and will be understood from Fig. 2 showing the line 1-1- along which the section shown in Fig. 1 is taken. On the opposite side of said rotor are arranged stationary catch nozzles 10 in substantial alignment with the steam nozzles 9, so that the steam which is passed "through the blade channels of the rotor 3 and has cooled such rotor (since the temperature 65 of the steam is considerably below that of the explosion gases) will enter the catch nozzles without becoming mixed with combustion gases. The steam flows through the catch nozzles 10 and pipes 10 connected therewith to suitable discharge nozzles 10" arranged at the inlet sidelof the intermediate pressure turbine 6. At the outlet side of the intermediate pressure turbine catch nozzles 12 are arranged in substantial alignment with the pipes or nozzle conduits 10 leading fromthe catch nozzles 10 to the intermediate pressure turbine. Since in turbines of the type illustrated in the drawings the steam travels in substantially axial direction, the catch nozzles take up the jets of steam issuing from the nozzle conduits 10', and are not entered by combustion gases; It will be seen that the arrangement is such that combustion gases from the exhaust chamber 5 and the steam from the catch nozzles 10 will be kept separate from each other during their passage through the intermediate pressure turbine 6. The steam will at this point also exert a cooling action on the turbine blades since the combustion gases passing through the intermediate turbine, while not so hot when they were at the high temperature turbine, are still of a temperature above that of the steam. It will be understood that each nozzle 9 has a catch nozzle 10 and a catch nozzle 12 and also a charging nozzle 13 associated therewith, only one such set of nozzles being shown in Fig.1 to avoid complicating the drawing. It is desirable to cool some of the stationary 100 arts of the plant and I have shown a cooling packet 11 surrounding the exhaust chamber 5 and the casing of the intermediate pressure turbine 6. Any suitable cooling medium may be passed through said jacket. I prefer to use steam for this purpose, for instance a portion of the steam supply from the boiler 7 is then conveyed through pipes 13 to a low pressure steam turbine 14, rom the outlet of which it passes to a condenser 15. The drawing shows only the nozzle 12 and the pipe 13 which are in alignment with ,the catch nozzle 10 illustrated, although two such nozzles 12 and pipes 13 are provided in correspondence with the two catch nozzles 10 that cooperate with the two steam nozzles 9. It will be seen that the high pressure turbine and the intermediate pressure turbine are driven both by steam and by combustion gases, while the low pressure turbine is driven by steam alone.

To give a specific example showing a suit-:-

able proportioning of the individual 'parts and illustrating the operation of the invention in connection'with fuel gas of predetermined quality, the following example will enable the conditions of actual practice to be understood more readily. In this example it has been assumed that the gas em loyed as fuel contains 500 thermal units a1.) .per cubic meter at the temperature of 0 C. and atmospheric pressure. In this case the pressure of the combustion gases at the point of their admissionto the explosion chamber 1 may be 6 atmospheres and their temperature 7 5 C. The maximum pressure which the combustion gases reach during explosion may be 35.4 atmospheres absolute and their temperature 17 00 C. At the point of the issue from the nozzles to the rotor 3, the combustion gases may have a pressure of 5.25 atmospheres .absolute and a temperature of 1110 C., the eificiency of this high pressure stage, so far as the combustion gases are concerned, being 70%, the speed of the combustion gases entering the high pressure stage about 880 meters er second, and the effective thermal drop equivalent to 89 Cal. per cubic meter. The exhaust gases from the chamber 5 enter the intermediate pressure turbine at a pressure of 5.25 atmospheres absolute and a" temperature of 1110 C. and leave the same at a pressure of 1.06 atmospheres and a temperature of about 725. The efliciency of the intermediate pressure stage, so far as the.

combustion gases are concerned, is about 82% and the-thermal drop equivalent to 138 Cal. per cubic meter. As regards steam, the

pressure of the steam delivered to the nozzles 9 may be 17 atmospheres absolute and its temperature 400 C. In the catch nozzles 10, the pressure of the steam is 5.25 atmospheres absolute. The efliciency of the high pressure stage, so far as steam is concerned, is The final temperature is 350 C. and the drop equivalent to 12 Cal. per cubic meter of fuel gas. At the intermediate pressure stage, the inlet pressure of the stage is 5.25 atmospheres and its temperature 300 C. Its outlet pressure is 1.06 atmospheres absolute and its outlet temperature 450 C. The efficiency is 82% and the drop 15 Cal. per. cubic meter. Finally, at the low pressure stage the'steam is admitted with 1 atmosphere absolute and a temperature of 450 C. and exhausts to'the condenser at a temperature of 155 C. and a pressure of .05 atmospheres absolute, the efficiency being 80%. The total effective thermal drop of steam from the high pressure stage to the condenser is 65 Cal. per cubic meter of fuel gas. The total drop per cubic meter of fuel gas therefore is 89+138+65=292 Cal.

The air and fuel are fed to the explosion chamber under compression, and the power for this compression is taken from the turbine. Assuming an efficiency of this compression would require 62 Cal. per cubic meter of fuel gas; Deducting this from the 292 Cal. mentioned above, there remains 230 Cal. available as useful load. As the heat supply has been'assumed to be 500 Cal. per cubic meter of fuel gas, it follows that the total net efiiciency at the point where the power of the engine is delivered to the driven machinery, for instance adynamo 16, will be 230 divided by 500, that is"46%.

Various changes in the specific forms shown and described may be made within the scope of the claims, without departing from the spirit of my invention.

I claim 1. A multistage gas turbine plant comprising an explosion chamber for the generation of combustion gases, a high pressure rotor operated by said gases, an exhaust chamber into which said gases issue from said. rotor, an intermediate pressure turbine the inlet of which communicates directly with said chamber, steam nozzles arranged to discharge steam against said rotor, catch nozzles located in said exhaust chamber and arranged to receive the steam after its passage through said rotor. discharge nozzles likewise arranged in said chamber and delivering steam to said intermediate pressure turbine, conduits arranged wholly in said exhaust chamber for conveying the steam from said catch nozzles to said discharge nozzles, means for collecting separately the combustion gases and the steam issuing from said intermediate pressure turbine, a low pressure condensing turbine actuated by the steam thus collected, a

I boiler heated by the combustion gases thus Lbs ' collected, and a connection from said boiler ing from both the-high pressure and interto said steam nozzles associated with the high mediate turblnes,

pressure rotor. In testimony whereof I have hereunto set 2. A multistage turbine plant comprising my hand.

5 a 'high pressure explosion turbine having HANS HOLZWARTH. 70

means ncluding an explosion chamber, for

discharging separately successive jets of combustion gases and another driving fluid against its rotor, an exhaust chamber into which said gases issue from said rotor, -an- 75 other turbine the inlet of which communicates directly with said exhaust chamber, catch, nozzles arranged in said exhaust chamber to receive the other driving fluid as it issues from the high pressure rotor, discharge 1102- 80 zles likewise arranged in said chamberand' delivering said fluid to thesecond turbine, and conduits arranged wholly in said chamber for conveying such fluid from said catch nozzles 'to said discharge nozzles. 85

3. A multistage turbine plant comprising a high pressure explosion turbine having means including an explosion chamber, for discharging separately successive jets of combustion gases and another driving fluid no against its rotor, an exhaust chamber into which said gases issue from said rotor, another turbine the inlet of which receives said gases from said exhaust chamber, catch nozzles arranged in said exhaust chamber to re 95 eive the other driving fluid as it issues from the high'pressure rotor, discharge nozzles arranged to deliver said second fluid to the second turbine, and conduit's'extending from said catch nozzles to said discharge nozzles [00 iand arranged wholly in said exhaust cham- 4;. A multistage turbine plant comprising a high pressure explosion turbine having means including an explosion chamber, for 105 discharging separately successive jets of combustion gases and another drivingfluid against its rotor, an exhaust chamber into Which said gases issue from said rotor, an

,5 intermediate turbine the inlet of which re- 110 ceives said gases from said exhaust chamber, catch nozzles arranged in said exhaust chamber to receive the other driving fluid as it issues from the high pressure rotor, disso charge nozzles arranged to deliver said second 115 fluid to the second turbine, conduits extending from said catch nozzles to said discharge nozzles and arranged wholly in said exhaust chamber, an exhaust chamber into which said gases issue from said intermediate turbine,

catch nozzles arranged to receive said other driving fluid as it issues from said intermediate turbine, a third turbine, discharge nozzles arranged to deliver said other driving fluid to said third turbine, and a conduit connecting said last mentioned catch and discharge nozzles and located in the exhaust chamber of said intermediate turbine, Whereby said other driving fluid travels in heatexchange relation with the gases exhaust 39 

